Abstract Severe mitral annular calcification is frequently encountered in patients with chronic renal failure requiring dialysis. The procedures are described for the implantation of mitral prostheses in two dialysis patients with mitral stenosis who exhibited heavily calcified mitral annuli. In both cases the calcifications extended around the entire mitral annulus as well as the valve leaflets, papillary muscle, atrial wall and ventricular myocardium, making it impossible to secure prosthetic valves to the mitral annuli. Before implantation, the calcification was partially debrided ultrasonically, and an 'atrioventricular channel' created. A mechanical valve with a polyester fabric collar was fixed on the atrial side of the calcified annulus using double sutures and gelatin-resorcin-formol glue. Perivalvular leakage, obstruction of valve opening or tortuous movements of prosthetic valve ring were not observed, and neither patient developed heart failure after surgery. This technique represents a potentially useful approach in the surgical treatment of patients with severely calcified mitral annuli.
Heart-lung transplantation (HLT), followed by single lung transplantation (SLT) and subsequently bilateral lung transplantation (BLT) have been developed as treatments for patients with end-stage pulmonary diseases. Initially, SLT was limited to idiopathic pulmonary fibrosis (IPF) cases and thought to be contraindicated not only for infectious diseases, but also for non-infectious diseases, including pulmonary emphysema (PE) and primary pulmonary hypertension (PPH), based on physiologic points of view. However, SLT is now widely performed for those non-infectious diseases and most of the recipients return to a normal active life. It is quite possible that BLT is superior to SLT in terms of pulmonary function, and it has been reported that BLT is better for PE and PPH patients in regards to perioperative course, postoperative exercise capacity, and long-term survival. For those situations and because of the present scarcity of donor organs, SLT must be utilized for selected non-infectious diseases for which it is safe and effective. When a single lung is replaced for IPF, PE, and PPH recipients, different physiologic situations are produced postoperatively, the understanding of which is extremely important to achieve good results, not only in the perioperative but also in the long term.
Experimental studies have demonstrated that adrenomedullin (AM) has a positive inotropic action and exerts inhibitory effects against ventricular remodelling as an autocrine and paracrine factor. However, there is no clinical evidence for AM acting as a local regulator in the human heart. We measured the levels of various molecular forms of AM, i.e. an active form of mature AM (AM-m), an intermediate inactive form of glycine-extended AM (AM-Gly) and total AM (AM-T = AM-m+AM-Gly), in plasma and pericardial fluid using our newly developed immunoradiometric assay in consecutive 67 patients undergoing coronary artery bypass graft surgery. Pericardial fluid and plasma cAMP, atrial natriuretic peptide and brain natriuretic peptide levels were also measured. The relationships between pericardial fluid AM levels and ventricular functions and other hormone levels were analysed. The level of each molecular form of AM in pericardial fluid was closely correlated with that of the other molecular forms of AM in the fluid. However, levels were not correlated with those in plasma. AM-T levels were slightly higher in pericardial fluid than in plasma (+72%; P<0.05), whereas AM-m levels and AM-m/AM-T ratios were markedly higher in pericardial fluid than in plasma (AM-m, +994%; AM-m/AM-T ratio, +443%; both P<0.01). AM-m, AM-Gly and AM-T levels in pericardial fluid were correlated with indices of left ventricular function, and with atrial natriuretic peptide and brain natriuretic peptide levels. Interestingly, AM and cAMP levels were positively correlated in plasma, but negatively correlated in pericardial fluid. In addition, AM-m, AM-Gly and AM-T levels in pericardial fluid were higher in patients with acute coronary syndrome than in those with stable ischaemic heart disease (AM-m, +80%; AM-Gly, +96%; AM-T, +83%; all P<0.01). These results suggest that AM in pericardial fluid reflects cardiac synthesis, and that enhanced cardiac secretion of AM is associated with left ventricular dysfunction, ventricular overload and myocardial ischaemia. Considering that AM has positive inotropic, coronary vasodilatory and anti-remodelling actions, increased cardiac AM may play a compensatory role in the ischaemic and failing myocardium.
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